This 250 km2 ice formation (30 km in length), is one of 48 glaciers fed by an ice field that is the world's third largest reserve of fresh water.
This particular glacier is located in a national park in South America and it was named after the explorer who studied the region in the 19th century. It`s one of only three glaciers in the area that is still growing and one of the most important tourist attractions in the area.
Rupture
Pressures from the weight of the ice slowly pushes the glacier over the southern arm of the nearby lake, damming the section and separating it from the rest of the lake. With no outlet, the water level on the that side of the lake can rise by as much as 30 meters above the level of the main body of the lake. Periodically, the pressure produced by the height of the dammed water breaks through the ice barrier causing a spectacular rupture, sending a massive outpouring of water to the main body of the lake.
Tourism
Due to its size and accessibility it is one of the major tourist attractions in southern Patagonia. Many tour companies run daily visits. A large visitor centre at the site features a walking circuit which allows visitors to view the southern flank and the east facing edge of the glacier.
In recent years, trekking tours on the ice have gained popularity. The two standard tours are a "mini-trekking" option, consisting of a short walk of about an hour and a half, and a "big ice" version, which is usually about five hours. Tour companies generally provide crampons to customers.
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